.. note::
    :class: sphx-glr-download-link-note

    Click :ref:`here <sphx_glr_download_cookbook_adaptive-steps.py>` to download the full example code
.. rst-class:: sphx-glr-example-title

.. _sphx_glr_cookbook_adaptive-steps.py:


Use scans with adaptive step sizes
**********************************

Problem
=======

Concentrate measurement in regions of high variability, taking larger strides
through flat regions.

Approach
========

The *plans* in bluesky can be fully adaptive, determining one step at a time.
A couple built-in plans provide this capability out of the box.

Example Solution
================

The :func:`bluesky.plans.adaptive_scan` aims to maintain a certain delta in y
between successive steps through x. After each step, it accounts for the local
derivative and adjusts it step size accordingly. If it misses by a large
margin, it takes a step backward (if allowed).



.. code-block:: default

    import matplotlib.pyplot as plt

    from bluesky import RunEngine
    from bluesky.plans import adaptive_scan
    from bluesky.callbacks import LivePlot
    from ophyd.sim import motor, det

    # Do this if running the example interactively;
    # skip it when building the documentation.
    import os
    if 'BUILDING_DOCS' not in os.environ:
        from bluesky.utils import install_qt_kicker  # for notebooks, qt -> nb
        install_qt_kicker()
        plt.ion()
        det.exposure_time = 0.5  # simulate slow exposures

    RE = RunEngine({})

    RE(adaptive_scan([det], 'det', motor,
                     start=-15,
                     stop=10,
                     min_step=0.01,
                     max_step=5,
                     target_delta=.05,
                     backstep=True),
       LivePlot('det', 'motor', markersize=10, marker='o'))




.. image:: /cookbook/images/sphx_glr_adaptive-steps_001.png
    :class: sphx-glr-single-img




Observe how the scan lengthens its stride through the flat regions, oversteps
through the peak, moves back, samples it with smaller steps, and gradually
adopts a larger stride as the peak flattens out again.


.. rst-class:: sphx-glr-timing

   **Total running time of the script:** ( 0 minutes  2.392 seconds)


.. _sphx_glr_download_cookbook_adaptive-steps.py:


.. only :: html

 .. container:: sphx-glr-footer
    :class: sphx-glr-footer-example



  .. container:: sphx-glr-download

     :download:`Download Python source code: adaptive-steps.py <adaptive-steps.py>`



  .. container:: sphx-glr-download

     :download:`Download Jupyter notebook: adaptive-steps.ipynb <adaptive-steps.ipynb>`


.. only:: html

 .. rst-class:: sphx-glr-signature

    `Gallery generated by Sphinx-Gallery <https://sphinx-gallery.github.io>`_